The present application claims priority under 35 U.S.C. xc2xa7119 of Finnish Patent Application No. 981598, filed on Jul. 13, 1998, the disclosure of which is expressly incorporated by reference herein in its entirety.
1. Field of the Invention
The present invention relates to a process for drilling holes in the shell of a cylinder such as a paper machine cylinder, without requiring removal of the cylinder from its operating position. The process utilizes a multispindle drilling apparatus including a device for controlling a distance between drill centers of adjacent drilling modules.
The present invention also relates to an apparatus for drilling holes in the shell of paper machine cylinder. The apparatus includes a stationary framework supportable on the paper machine and a feed frame movable along the stationary framework radially toward the shell of the cylinder. The feed frame is coupled to a plurality of drilling modules that are adapted for rotation via a drive unit.
2. Discussion of Background Information
Several types of equipment are known in the art for drilling holes in the shell of a cylinder in a paper machine. Examples of some embodiments of this type of equipment are disclosed in, e.g., patent publications EP-B-0448947 and EP-B-0545879.
In EP-B-0448947, a method and an apparatus are disclosed for on-site drilling of perforating holes in the shell of a cylinder, e.g., a dryer cylinder, in a paper machine, in which the cylinder need not be removed from the paper machine. The apparatus includes a spindle box equipped with a plurality of spindle heads adapted to be driven by a drive motor. The spindle box houses the drive motor which is arranged to move the spindle box relative to a framework of the drilling apparatus when the drills are actuated toward the cylinder surface to be machined. Further, the apparatus includes a drilling jig to support and tension the framework of the drilling apparatus between guideways and the shell of the cylinder to be machined. Further, the apparatus includes slide bushings arranged to guide the framework of the drilling apparatus along the guideway assembly when the apparatus is being moved into a next drilling position in the direction of the cylinder axis. The design of the apparatus uses guideways supported on the cylinder next to the cylinder being machined.
In EP-B-0545879, a further development of the above-outlined apparatus is disclosed in which each spindle head is provided with a separate slide frame that is adapted to be individually movable in the lateral direction.
These prior art apparatuses are hampered, among other drawbacks, by their complicated construction which results in, e.g., a limited range of spindle head movement. Furthermore, the system requires the use of a drilling jig, such that each different drilling pattern requires an individual drilling jig.
The present invention provides an entirely novel type of process and apparatus for drilling holes the shell of a cylinder in which the above-noted drawbacks of the prior art techniques are overcome.
The invention provides a multispindle drilling apparatus that includes drilling modules having at least two spindle heads. Moreover, a mutual distance of (i.e., a distance between) spindle shaft centers in each drilling module is adjustable by rotating the spindle heads of at least one drilling module about a respective intermediate shaft of the drilling module.
In an exemplary embodiment of the present invention, a process for setting a drilling pattern includes rotating one of a body of the drilling module or the drilling head of the drilling module about a central drive shaft of the drilling module.
The process can further include altering a mutual position of adjacent drilling modules with respect to each other.
The apparatus of the present invention includes drilling modules having at least two spindle heads. At least one spindle head in each drilling module is rotatable about an intermediate shaft of the drilling module.
In the exemplary embodiment of the apparatus, one of the drilling module or the spindle head is rotatable about the central drive shaft of the module. The apparatus can also include locking devices to hold the module or head into a desired position.
In a further embodiment, a feed frame of the apparatus can be coupled to a plurality of drilling modules and at least some of the modules can be arranged for movement in the lateral direction.
The process and apparatus according to the present invention offer a number of significant benefits. For example, the use of multispindle drilling modules and the positioning of the drilling modules as well as the positioning of the spindle heads within each drilling module via rotation about respective intermediate shafts can provide an extremely wide latitude in the position control of the drilling modules. The position control possibilities may be further extended by using drilling modules adapted to be rotatable about the central drive shaft of the module. Thus, the present invention facilitates drilling without requiring drilling jigs.
The present invention relates to a process for operating an apparatus to drill holes in the shell of a cylinder, such as a paper machine cylinder. The apparatus includes a multispindle drilling arrangement having a plurality of drilling modules with at least two spindle heads and a device for controlling a distance between drill centers of adjacent drilling modules. The process includes rotating at least one of the at least two spindle heads about a respective intermediate shaft of the drilling module arranged between a drive shaft and the at least one spindle head, such that a mutual distance between spindle shaft centers of the at least two spindle heads in the drilling modules is adjusted.
According to a feature of the present invention, the process can include rotating at least one of a body of the drilling modules and a drilling head of the drilling module about a central drive shaft of the drilling module.
In accordance with another feature of the invention, the process can further include altering a mutual positioning between adjacent drilling modules with respect to each other.
In accordance with still another feature of the instant invention, the process can further include aligning the at least two spindle heads to be parallel to an axis of the cylinder to be drilled.
According to a further feature of the invention, the process may further include moving the at least two spindle heads in a direction toward the surface of the cylinder to be drilled.
According to still another feature of the present invention, the process can include driving each of the at least two spindle heads with a single drive device.
In accordance with a still further feature of the instant invention, the process can include driving each of the at least two spindle heads with a single drive train.
In accordance with another feature of the present invention, the process can further include securing the at least one of the at least two spindle heads, such that the mutual distance between spindle shaft centers of the at least two spindle heads is held constant.
The present invention also relates to an apparatus for drilling holes in the shell of paper machine cylinder. The apparatus includes a stationary framework supportable on the paper machine, a feed frame that is radially movable along the stationary framework relative to the shell, a drive unit, a plurality of drilling modules coupled to the feed frame, which are rotatable via the drive unit. The drilling modules include a drive shaft, at least two spindle heads, and at least two intermediate shafts arranged between the drive shaft and the at least two heads, in which at least one of the at least two spindle heads in each drilling module is rotatable about a respective shaft of each drilling module.
According to a feature of the instant invention, at least one of the drilling module and a drilling head of the drilling module can be rotatable about a central drive shaft of the drilling module. Further, a locking device can be provided for fixing the one of the drilling module and the drilling head into a desired position.
In accordance with a further feature of the present invention, at least one of the plurality drilling modules may be movable in a lateral direction.
In accordance with still another feature of the invention, an actuation device can move the feed frame toward a surface of the cylinder to be drilled.
According to another feature of the present invention, the stationary frame can include at least one guideway, and the feed frame may be slidably coupled to the at least one guideway.
According to still another feature of the instant invention, each drilling module can include a drive pulley coupled to a respective drive shaft, and each drive shaft may be concentrically arranged along a respective central axis of the drilling modules. Further, a first gear can be positioned to couple the drive shafts to the respective intermediate shafts. Still further, the first gear can be coupled to the drive shaft for driving the at least one of the at least two spindle heads. Further still, a drive belt can be positioned to drive each drive shaft via the drive unit.
The present invention also relates to an apparatus for drilling holes in the shell of paper machine cylinder. The apparatus includes a plurality of drilling modules, and the plurality of drilling modules include a drive shaft, at least two spindle heads, and at least two intermediate shafts arranged between the drive shaft and the at least two spindle heads, in which at least one of the at least two spindle heads in each drilling module is rotatable about a respective intermediate shaft of the drilling modules.
According to yet another feature of the instant invention, a coupling device can be coupled to the plurality of drilling modules adjacent to a cylinder in a material web production machine to be drilled. During drilling, the cylinder to be drilled is located in an operational position within the material web production machine.
Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.